There are a number of social networks, each of which may have its own social graph representing the social network. A social graph may comprise multiple nodes, each node representing an entity, e.g., a user, and multiple edges, each edge connecting a pair of nodes and representing a relationship between the pair of nodes, or entities. There is no requirement for a user's information available on one social network to coincide with information known about the same user on another social network.
Additionally, information about a user available from multiple, different information sources may not be associated making it difficult, if not impossible, to relate one item of information about the user with another item of information about the user.